Retaining wall block and system

ABSTRACT

A retaining wall block for an engineered block retaining wall system having an integrally formed head, neck and body, in which one generally planar front face of the body forms a visible part of the wall, the body having two pin holes, two clean out holes, each of which terminates within the body of the block, and two pin receiving openings, the pin receiving openings being configured to receive a free end of a lock pin provided in a pin hole of a block placed there under so as to interlock the blocks with a predetermined setback. The pin holes and pin receiving openings being positioned such that a plane extending perpendicular to the generally planar front face passes through one, and only one, of said pin holes or said pin receiving openings.

This is a continuation in part of application Ser. No. 11/905,680, filed Oct. 3, 2007, the contents of which are hereby incorporated by reference.

FIELD OF THE INVENTION

This relates to the field of retaining walls and the blocks used to construct retaining walls.

BACKGROUND

Retaining walls have been traditionally constructed using natural stone, landscape timbers, masonry block, poured concrete or railroad ties. More recently, engineered concrete block retaining systems have been introduced to the market. Those systems, exemplified by U.S. Pat. No. 7,011,474 to MacDonald, do not use mortar to lock the individual blocks into position but rely instead on methods of locking blocks into position, including specially formed pins. These lock pins include a relatively small diameter body portion that fits into holes formed in the blocks that form a lower course of a retaining wall and a relatively large diameter head portion that sits on top of the block. The next course of block is laid such that the larger diameter head of the lock pin fits into grooves formed in the bottom of the blocks that form the next course of block. Thus, the lock pin secures the two courses together. Other engineered concrete block retaining systems are shown in U.S. Pat. Nos. Re. 34,314, and 4,914,876 (both to Forsberg); U.S. Pat. No. 5,294,216 (to Sievert); and U.S. Pat. No. 7,168,892 (to MacDonald).

These products have become popular because they are easy to install, very durable, and can be used to create structurally sound retaining walls at great cost savings. We now describe a retaining wall block that eliminates the need for locking pins having a large diameter head and small diameter body and reduces the weight of the engineered retaining wall block while maintaining the structural integrity of the block and the retaining walls formed of such blocks.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of the top surface of a retaining wall block;

FIG. 2 is a plan view of the bottom surface of the retaining wall block illustrated in FIG. 1;

FIG. 3 is a perspective view of a retaining wall block;

FIG. 4 is a top view of three interlocked retaining wall blocks;

FIG. 5 is a partial front perspective view of a retaining wall built of retaining wall blocks;

FIGS. 6A and 6B are top views of alternate ways of laying a first course of five retaining wall blocks;

FIG. 7 is a plan view of a second embodiment of a retaining wall block; and

FIG. 8 is a plan view of a third embodiment of a retaining wall block.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EXEMPLARY EMBODIMENTS

Referring to FIGS. 1 to 3, an engineered retaining wall block 1 is shown.

Block 1 is preferably made of pre-cast concrete, although other suitable materials may be substituted for the concrete. Block 1 has three integrally formed parts, a body 2, a neck 3 and a head 4. The neck 3 connects the body 2 to the head 4. The body 2, neck 3, and head 4 all extend between top surface 5 and a bottom surface 6. The top and bottom surfaces 5 and 6 form planes that are essentially parallel to one another. Once block 1 is installed as part of a retaining wall, the forward face 7 of body 2 remains visible as part of the wall.

The neck 3 and head 4 are formed to reduce the weight of block 1, while maintaining structural integrity and support. Body 2 forms the greatest part of block 1, with a width of approximately one and ½ feet, a depth of just over 4 inches, and a height of 8 inches. Neck 3 is long and narrow by comparison. Neck 3 is narrowed about 4 inches on each side of body 2 so as to remain centered on body 2 and to create shoulder portions 8 and 9 on each side of body 2. The cross-section of neck 3 is thus reduced to approximately half the cross-section of body 2. Neck 3 extends approximately five and ¾ inches in depth. The weight of neck 3 is further reduced by forming a rectangular-shaped opening 10 that extends through the neck 3 from the top surface 5 to the bottom surface 6 of block 1. Opening 10 is molded to be approximately 5 inches wide and 6 inches deep, and centered within neck 3. The forward-most wall 11 of opening 10 is approximately co-planar with shoulders 8 and 9.

First and second receiving openings 12 and 13 are formed in the body 2 and extend from the top surface 5 to the bottom surface 6. In the preferred embodiment, each of these openings is approximately one and ⅛ inches thick and 2¾ inches wide. The receiving openings 12 and 13 are wide and long enough to ease installation and to account for variations encountered on-site when laying a wall. The extension of receiving openings 12 and 13 through block 1 from the top surface 5 to the bottom surface 6 saves material costs and effectively reduces block weight so as to further ease placement and installation.

First and second pin holes 14 and 15 are formed in the body 2. These pin holes are approximately 9/16 inches in diameter and extend approximately 2½ inches into body 2. These pin holes are designed to accept insertion of pins which are used to interlock block 1 in position with one or more blocks placed above. Pin holes 14 and 15 are also formed to include clean out holes 31 and 32, respectively, which are of smaller diameter than the pin holes 14 and 15. In one embodiment, the clean out holes 31 and 32, shown in FIGS. 1-3, are round, 7/16 inch in diameter, 2½ in depth, and are designed to avoid debris accumulation in pin holes 14 and 15. In another preferred embodiment, the pin holes 14 and 15 are ⅝ inch round and extend 4½ inches deep and the clean out holes 31 ands 32 are ⅜ inch round and 2¾ inches deep. During installation, pins 16 and 17 are placed into pin holes 14 and 15. FIG. 3 shows the pins 16 and 17 inserted into block 1. Without clean out holes 14 and 15, debris can accumulate in the pin holes 14 and 15 and interfere with the proper seating of pins 16 and 17 within the pin holes.

The pins 16 and 17 are preferably constructed of fiberglass dowel of 9/16 inches diameter and 5 inch height. Those of skill in the art understand that other sizes and constructions would also be suitable, for example rebar steel or other suitable materials can be substituted for fiberglass. The pin holes 14 and 15 are placed relative to the placement of the receiving openings 12 and 13 so the block 1, when installed, functions together with its neighbors to provide a structurally sound, engineered retaining wall system.

In the preferred embodiment, the rearmost inner walls 18 and 19 of openings 12 and 13, respectfully, are spaced 1¼ inches forwardly of the forward most wall 11 of opening 10. By contrast, the pin holes 14 and 15 are positioned 1 inch forward of that same wall. Through this relative placement, each block 1 is secured in place on top of the blocks that form the lower course, leaving a ¼ of an inch setback for each successive course of blocks. The setback can be strategically greater or less depending on the appearance of the wall desired. This setback is shown in FIG. 4.

FIG. 4 also shows how the placement of the pin holes 14 and 15 relative to receiving openings 12 and 13 enhances the structural integrity by offsetting the pin holes 14 and 15 from the receiving openings 12 and 13. As best shown in FIG. 4, pin holes 14 and 15 are positioned such that no plane perpendicular to the front face 7 of block 1 ever runs through both pin hole 14 and receiving opening 12 or pin hole 15 and receiving opening 13. Such a plane could run through one or the other, but not both. As also shown in FIG. 4, the relative placement of the pin holes and the receiving openings in body 2 causes the legs 18 and 19 of neck 3 of each successive course of block 1 to be offset. Thus, just as the front face 7 of block 1 will not align with the face of the block above or below that block, neither leg 18 nor leg 19 of block 1 will not align with leg 20 of block 100 or leg 21 of block 200. This offset construction provides structural integrity without interfering with water drainage through opening 10.

The assembly of blocks to form a retaining wall is best described with reference to FIGS. 4 and 5. The lower course of a wall is formed by blocks 100 and 200. Those blocks are constructed the same way as block 1, described in connections with FIGS. 1-3, above. Locking pins 16 and 17 are shown in pin holes 14 and 15 of block 100 and block 200, respectively. Block 1 is shown on top of blocks 100 and 200 such that pin 16 in block 100 is engaged with the rearmost wall 18 of receiving opening 12 and pin 17 in block 200 is engaged with the rearmost wall 19 of receiving opening 13. FIG. 4 illustrates how block 1 is secured in place so as to create a minimum setback of approximately ¼ of an inch while ensuring leg 18 of block 1 does not align with leg 20 of block 100 below. This construction provides a 1-2% setback for each successibe course of wall blocks.

FIG. 5 shows a retaining wall 30 created by installing block 1 as described in connection with FIG. 4. As those of skill in the art will appreciate from this drawing, block 1 can be broken in half to finish wall 30.

FIG. 1 also shows ear portions 22 and 23 of head 4 and angled wall portions 24 and 25 of body 2. Ear portions 22 and 23 are formed during the manufacturing process to allow the blocks to be pushed off conveyor belts during the packing process without causing the blocks to roll over while being pushed. That is, the ear portions provide a layer surface to push on when the blocks are shoved off of conveyor belts during a packing operation.

During installation, ear portions 22 and 23 can be reduced in size or knocked off entirely to facilitate placement of a row of blocks 1 in a convex shaped retaining wall as shown in FIG. 6A. The ability of block 1 to be formed in a convex wall shape is also facilitated by the provision of angled side walls 24 and 25 on body 2. As an alternative, block 1 can be placed as shown in FIG. 6B to create a concave shaped retaining wall. In the case of a convex shaped retaining wall, the retention of ear portions 22 and 23 is immaterial. The size, shape and placement of receiving openings 12 and 13 relative to pin holes 14 and 15 facilitates the placement of block 1 in a concave or convex shaped pattern, while still providing for setback for each successive block course.

FIG. 7 shows a further embodiment of the invention. In this embodiment, the pin receiving cavities 42 and 43 are formed by arcuate walls 44 and 47 in a kidney shape. The block of FIG. 7 also differs from the block of FIGS. 1-5 in other respects. To facilitate the creation of a convex wall like that shown in FIG. 6A, the block of FIG. 7 is formed such that side walls 48 and 49 of the body portion of the block are angled inward to facilitate the placement of an adjoining block at the angel necessary to create a convex wall. That inward angle of side wall 48 creates a plane P₁ which, if extended to the head portion of the block, defines the outmost extension of ear 50. This reduced length of ear 50 further facilitates the creation of a convex wall shown in FIG. 6A and reduces the need to break off the ear portion 50.

FIG. 8 shows a further embodiment of the invention. In this embodiment, the block 50 is approximately 8 inches in height from a top surface 58 to a bottom surface (not shown), 12 inches in depth and 18 inches in length. Pin holes 52 and 54 are ⅝ inch square, and clean out holes 53 and 57 are ⅜ inch square. Pin holes 52 and 54 terminate within block 50 approximately 4 inches from the top surface 58, and the clean out holes terminate within the block approximately 7 inches from top surface 58. Pin receiving cavities 63 and 64 are depicted as having a generally rectangular shape, but may be formed in the kidney shape of pin receiving cavities 42 and 43 of FIG. 7 or other suitable shape, such as an inverted triangle. The legs 55 and 56 of block 50 are angled so as to form an opening 51 having an inverted trapezoidal shape.

As shown in FIG. 8, the outermost wall 59 of leg 56 extends between head portion 62 of block 50 and a body portion 61 of that block such that the plane P₂ created by that wall on one side of a centerline C_(L) does not extend through either the pin hole 52 or the pin receiving cavity 63. Similarly, a plane P₃ created by wall 60 on an opposite side of said centerline C_(L) does not extent through either the pin hole 54 of the pin receiving cavity 64. Further, the pin holes 52, 54 and pin receiving cavities 63, 64, are placed so as to be position in the body portion of the block between the P2 and P₃ planes. In this embodiment, the wedge shape crated by legs 55 and 56 enables the use of a head portion 62 that is shorter in overall length than body portion 61 without sacrificing the strength or stability of block 50. This construction also minimizes the need to trim away any ears formed on wall block 50 in order to form a convex wall as shown by FIG. 6A.

Irrespective of the size or shape of the wall constructed by serial placement of blocks 1 or 50, the depth and resultant stability of the wall is increased by including both neck 3 and head 4. In application, openings 10, 41, 51 and the spacing between legs 18 and 19, 45 and 46, and 55 and 56 of adjacent blocks in the same row can be filled with gravel to further anchor the wall to the hillside while facilitating the drainage of water there through without harm to the integrity of the resulting retaining wall structure.

Various aspects of the different embodiments can be combined in different combinations to create new embodiments. While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. 

1. A retaining wall block having a top surface and a bottom surface and a generally planar front face designed to form a portion of a front wall of a modular retaining wall system comprising: a body portion having said generally planar front face; a neck portion; a head portion; said body, neck and head portions being integrally formed and each having a defined width, said width of said body portion being greater than said width of said head portion, and said width of said head portion being greater than said width of said neck portion, said neck portion formed to have an opening extending from said top surface to said bottom surface, said opening dividing said neck portion to define two legs which connect said head portion to said body portion; first and second openings in said body portion extending between said top and said bottom surfaces defining first and second lock pin receiving openings; and first and second pin holes in said body portion and opening on said top surface, said pin holes being designed to accept a lock pin, said pin holes terminating within said body; and first and second clean out holes provided in the body portion below the first and second pin holes, said clean out holes being designed to avoid blockage of said pin holes by accumulation of debris said first and second clean out holes terminating within said body at least a half of an inch above said block bottom surface; wherein said first and second openings in said body portion are each configured to receive a free end of a lock pin provided in a pin hole of a block placed thereunder so as to interlock the blocks with a predetermined setback, and wherein a plane extending perpendicular to said generally planar front face passes through one of said pin holes or said pin receiving openings.
 2. The retaining wall block of claim 1 in which said body, neck and head are formed of poured concrete.
 3. The retaining wall block of claim 1 in which said opening in said neck forms two legs which connect said head to said body portion, wherein said pin holes and said pin receiving openings are configured such when said block is interlocked with one or more blocks thereunder, said legs of said block do not align with a leg of said block thereunder.
 4. The retaining block of claim 1 wherein said body further includes side walls which taper from said generally planar front face and said head include first and second ears which can be removed to facilitate formation of a convex shaped wall.
 5. The retaining wall block of claim 1 in which the first and second clean out holes terminate within said body an inch above said block bottom surface.
 6. The retaining wall block of claim 1 in which the first and second openings are kidney shaped.
 7. The retaining wall block of claim 1 in which said body portion includes a side surface formed to create an inner angle between a surface plane created by said side surface and said generally planar front face not greater than 80 degrees, and said head portion is limited in length so as to not extend beyond said plane created by said side surface.
 8. A retaining wall block having a top surface and a bottom surface and a generally planar front face designed to form a portion of a front wall of a modular retaining wall system comprising: a body portion having said generally planar front face; a neck portion; a head portion; said body, neck and head portions being integrally formed and each having a defined width, said width of said body portion being greater than said width of said head portion, and said width of said head portion being greater than said width of said neck portion, said neck portion formed to have an opening extending from said top surface to said bottom surface, said opening dividing said neck portion to define two legs which connect said head portion to said body portion; said wall block having an axis of symmetry extending perpendicular to said generally planar front face and dividing said wall block into two roughly equal sides and wherein each of said neck portion legs are angled away from said axis of symmetry such that said opening formed in said neck portion is in the form of an inverted trapezoid; each of said neck portion legs including an outer surface, each of said outer surfaces define a plane; first and second lock pin receiving openings in said body portion extending between said top and said bottom surfaces; and first and second pin holes in said body portion and opening on said top surface, said pin holes being designed to accept a lock pin, said pin hole terminating within said body; and first and second clean out holes provided in the body portion below the first and second pin holes, said clean out holes being designed to avoid blockage of said pin holes by accumulation of debris said first and second clean out holes terminating within said body at least a half of an inch above said block bottom surface; wherein said first and second openings in said body portion are each configured to receive a free end of a lock pin provided in a pin hole of a block placed there under so as to interlock the blocks with a predetermined setback, and wherein each of said planes defined by said outer surface of said neck portion legs extends from said head portion to said body portion of said wall block at an acute angle to said axis of symmetry and each of said planes extend through said body portion of said wall block at a location spaced away from said first and second lock pin receiving openings and said first and second pin holes.
 9. The retaining wall block of claim 8 in which said body, neck and head are formed of poured concrete.
 10. The retaining wall block of claim 8 in which said first and second pin holes and said first and second clean out holes are square shaped and designed to receive a square shaped lock pin.
 11. The retaining wall block of claim 8 in which said body width is greater than said head width.
 12. The retaining wall block of claim 8 in which said first and second pin holes and said lock pin receiving openings are positioned within said body portion of said block between said planes defined by said outer surfaces of said neck portion legs. 